dm thin: dont use map_context
This patch removes endio_hook_pool from dm-thin and uses per-bio data instead.
This patch removes any use of map_info in preparation for the next patch
that removes map_info from bio-based device mapper.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
diff --git a/drivers/md/dm-thin.c b/drivers/md/dm-thin.c
index 4b94074..e7743c6 100644
--- a/drivers/md/dm-thin.c
+++ b/drivers/md/dm-thin.c
@@ -186,7 +186,6 @@
struct dm_thin_new_mapping *next_mapping;
mempool_t *mapping_pool;
- mempool_t *endio_hook_pool;
process_bio_fn process_bio;
process_bio_fn process_discard;
@@ -304,7 +303,7 @@
bio_list_init(master);
while ((bio = bio_list_pop(&bios))) {
- struct dm_thin_endio_hook *h = dm_get_mapinfo(bio)->ptr;
+ struct dm_thin_endio_hook *h = dm_per_bio_data(bio, sizeof(struct dm_thin_endio_hook));
if (h->tc == tc)
bio_endio(bio, DM_ENDIO_REQUEUE);
@@ -375,7 +374,7 @@
if (bio->bi_rw & REQ_DISCARD)
return;
- h = dm_get_mapinfo(bio)->ptr;
+ h = dm_per_bio_data(bio, sizeof(struct dm_thin_endio_hook));
h->all_io_entry = dm_deferred_entry_inc(pool->all_io_ds);
}
@@ -485,7 +484,7 @@
static void overwrite_endio(struct bio *bio, int err)
{
unsigned long flags;
- struct dm_thin_endio_hook *h = dm_get_mapinfo(bio)->ptr;
+ struct dm_thin_endio_hook *h = dm_per_bio_data(bio, sizeof(struct dm_thin_endio_hook));
struct dm_thin_new_mapping *m = h->overwrite_mapping;
struct pool *pool = m->tc->pool;
@@ -714,7 +713,7 @@
* bio immediately. Otherwise we use kcopyd to clone the data first.
*/
if (io_overwrites_block(pool, bio)) {
- struct dm_thin_endio_hook *h = dm_get_mapinfo(bio)->ptr;
+ struct dm_thin_endio_hook *h = dm_per_bio_data(bio, sizeof(struct dm_thin_endio_hook));
h->overwrite_mapping = m;
m->bio = bio;
@@ -784,7 +783,7 @@
process_prepared_mapping(m);
else if (io_overwrites_block(pool, bio)) {
- struct dm_thin_endio_hook *h = dm_get_mapinfo(bio)->ptr;
+ struct dm_thin_endio_hook *h = dm_per_bio_data(bio, sizeof(struct dm_thin_endio_hook));
h->overwrite_mapping = m;
m->bio = bio;
@@ -899,7 +898,7 @@
*/
static void retry_on_resume(struct bio *bio)
{
- struct dm_thin_endio_hook *h = dm_get_mapinfo(bio)->ptr;
+ struct dm_thin_endio_hook *h = dm_per_bio_data(bio, sizeof(struct dm_thin_endio_hook));
struct thin_c *tc = h->tc;
struct pool *pool = tc->pool;
unsigned long flags;
@@ -1051,7 +1050,7 @@
if (bio_data_dir(bio) == WRITE && bio->bi_size)
break_sharing(tc, bio, block, &key, lookup_result, cell);
else {
- struct dm_thin_endio_hook *h = dm_get_mapinfo(bio)->ptr;
+ struct dm_thin_endio_hook *h = dm_per_bio_data(bio, sizeof(struct dm_thin_endio_hook));
h->shared_read_entry = dm_deferred_entry_inc(pool->shared_read_ds);
inc_all_io_entry(pool, bio);
@@ -1226,7 +1225,7 @@
spin_unlock_irqrestore(&pool->lock, flags);
while ((bio = bio_list_pop(&bios))) {
- struct dm_thin_endio_hook *h = dm_get_mapinfo(bio)->ptr;
+ struct dm_thin_endio_hook *h = dm_per_bio_data(bio, sizeof(struct dm_thin_endio_hook));
struct thin_c *tc = h->tc;
/*
@@ -1359,17 +1358,14 @@
wake_worker(pool);
}
-static struct dm_thin_endio_hook *thin_hook_bio(struct thin_c *tc, struct bio *bio)
+static void thin_hook_bio(struct thin_c *tc, struct bio *bio)
{
- struct pool *pool = tc->pool;
- struct dm_thin_endio_hook *h = mempool_alloc(pool->endio_hook_pool, GFP_NOIO);
+ struct dm_thin_endio_hook *h = dm_per_bio_data(bio, sizeof(struct dm_thin_endio_hook));
h->tc = tc;
h->shared_read_entry = NULL;
h->all_io_entry = NULL;
h->overwrite_mapping = NULL;
-
- return h;
}
/*
@@ -1386,7 +1382,7 @@
struct dm_bio_prison_cell *cell1, *cell2;
struct dm_cell_key key;
- map_context->ptr = thin_hook_bio(tc, bio);
+ thin_hook_bio(tc, bio);
if (get_pool_mode(tc->pool) == PM_FAIL) {
bio_io_error(bio);
@@ -1595,14 +1591,12 @@
if (pool->next_mapping)
mempool_free(pool->next_mapping, pool->mapping_pool);
mempool_destroy(pool->mapping_pool);
- mempool_destroy(pool->endio_hook_pool);
dm_deferred_set_destroy(pool->shared_read_ds);
dm_deferred_set_destroy(pool->all_io_ds);
kfree(pool);
}
static struct kmem_cache *_new_mapping_cache;
-static struct kmem_cache *_endio_hook_cache;
static struct pool *pool_create(struct mapped_device *pool_md,
struct block_device *metadata_dev,
@@ -1696,13 +1690,6 @@
goto bad_mapping_pool;
}
- pool->endio_hook_pool = mempool_create_slab_pool(ENDIO_HOOK_POOL_SIZE,
- _endio_hook_cache);
- if (!pool->endio_hook_pool) {
- *error = "Error creating pool's endio_hook mempool";
- err_p = ERR_PTR(-ENOMEM);
- goto bad_endio_hook_pool;
- }
pool->ref_count = 1;
pool->last_commit_jiffies = jiffies;
pool->pool_md = pool_md;
@@ -1711,8 +1698,6 @@
return pool;
-bad_endio_hook_pool:
- mempool_destroy(pool->mapping_pool);
bad_mapping_pool:
dm_deferred_set_destroy(pool->all_io_ds);
bad_all_io_ds:
@@ -2607,6 +2592,7 @@
ti->num_flush_requests = 1;
ti->flush_supported = true;
+ ti->per_bio_data_size = sizeof(struct dm_thin_endio_hook);
/* In case the pool supports discards, pass them on. */
if (tc->pool->pf.discard_enabled) {
@@ -2653,7 +2639,7 @@
union map_info *map_context)
{
unsigned long flags;
- struct dm_thin_endio_hook *h = map_context->ptr;
+ struct dm_thin_endio_hook *h = dm_per_bio_data(bio, sizeof(struct dm_thin_endio_hook));
struct list_head work;
struct dm_thin_new_mapping *m, *tmp;
struct pool *pool = h->tc->pool;
@@ -2683,8 +2669,6 @@
}
}
- mempool_free(h, pool->endio_hook_pool);
-
return 0;
}
@@ -2813,14 +2797,8 @@
if (!_new_mapping_cache)
goto bad_new_mapping_cache;
- _endio_hook_cache = KMEM_CACHE(dm_thin_endio_hook, 0);
- if (!_endio_hook_cache)
- goto bad_endio_hook_cache;
-
return 0;
-bad_endio_hook_cache:
- kmem_cache_destroy(_new_mapping_cache);
bad_new_mapping_cache:
dm_unregister_target(&pool_target);
bad_pool_target:
@@ -2835,7 +2813,6 @@
dm_unregister_target(&pool_target);
kmem_cache_destroy(_new_mapping_cache);
- kmem_cache_destroy(_endio_hook_cache);
}
module_init(dm_thin_init);